Manufactured cylinders are employed in a number of applications. One such application is the use of stents in the treatment of cardiovascular conditions. Stents are generally small, hollow cylinders formed from a metal lattice structure that may be inserted into an artery to hold it open and allow blood to flow. Stents may be manufactured with a variety of dimensions depending on their application. Stents may also be coated with drugs in order to aid in the treatment of a disease or condition.
The ability to quickly and accurately inspect stents and other cylinders for defects is an important part of the process of manufacturing such devices. In some applications, the required tolerances and/or regulations may be extremely demanding. Additionally, the small dimension of some cylinders (such as stents) can make visual inspection extremely challenging and time consuming. Furthermore, in addition to manufacturing defects, drug coating on stents introduces the possibility for other defects. For example, the coating may pool between gaps in the lattice structure, or may allow a foreign object (such as dust or a polymer strand) to adhere to the stent. The embodiments of the present invention address these as well as other needs.